lv_draw.h

Defines

LV_DRAW_UNIT_NONE
LV_DRAW_UNIT_IDLE

Enums

enum lv_draw_task_type_t

Values:

enumerator LV_DRAW_TASK_TYPE_NONE
enumerator LV_DRAW_TASK_TYPE_FILL
enumerator LV_DRAW_TASK_TYPE_BORDER
enumerator LV_DRAW_TASK_TYPE_BOX_SHADOW
enumerator LV_DRAW_TASK_TYPE_LABEL
enumerator LV_DRAW_TASK_TYPE_IMAGE
enumerator LV_DRAW_TASK_TYPE_LAYER
enumerator LV_DRAW_TASK_TYPE_LINE
enumerator LV_DRAW_TASK_TYPE_ARC
enumerator LV_DRAW_TASK_TYPE_TRIANGLE
enumerator LV_DRAW_TASK_TYPE_MASK_RECTANGLE
enumerator LV_DRAW_TASK_TYPE_MASK_BITMAP
enumerator LV_DRAW_TASK_TYPE_VECTOR
enum lv_draw_task_state_t

Values:

enumerator LV_DRAW_TASK_STATE_WAITING
enumerator LV_DRAW_TASK_STATE_QUEUED
enumerator LV_DRAW_TASK_STATE_IN_PROGRESS
enumerator LV_DRAW_TASK_STATE_READY

Functions

void lv_draw_init(void)

Used internally to initialize the drawing module

void lv_draw_deinit(void)

Deinitialize the drawing module

void *lv_draw_create_unit(size_t size)

Allocate a new draw unit with the given size and appends it to the list of draw units

参数:

size -- the size to allocate. E.g. sizeof(my_draw_unit_t), where the first element of my_draw_unit_t is lv_draw_unit_t.

lv_draw_task_t *lv_draw_add_task(lv_layer_t *layer, const lv_area_t *coords)

Add an empty draw task to the draw task list of a layer.

参数:
  • layer -- pointer to a layer

  • coords -- the coordinates of the draw task

返回:

the created draw task which needs to be further configured e.g. by added a draw descriptor

void lv_draw_finalize_task_creation(lv_layer_t *layer, lv_draw_task_t *t)

Needs to be called when a draw task is created and configured. It will send an event about the new draw task to the widget and assign it to a draw unit.

参数:
  • layer -- pointer to a layer

  • t -- pointer to a draw task

void lv_draw_dispatch(void)

Try dispatching draw tasks to draw units

bool lv_draw_dispatch_layer(lv_display_t *disp, lv_layer_t *layer)

Used internally to try dispatching draw tasks of a specific layer

参数:
  • disp -- pointer to a display on which the dispatching was requested

  • layer -- pointer to a layer

返回:

at least one draw task is being rendered (maybe it was taken earlier)

void lv_draw_dispatch_wait_for_request(void)

Wait for a new dispatch request. It's blocking if LV_USE_OS == 0 else it yields

void lv_draw_dispatch_request(void)

When a draw unit finished a draw task it needs to request dispatching to let LVGL assign a new draw task to it

lv_draw_task_t *lv_draw_get_next_available_task(lv_layer_t *layer, lv_draw_task_t *t_prev, uint8_t draw_unit_id)

Find and available draw task

参数:
  • layer -- the draw ctx to search in

  • t_prev -- continue searching from this task

  • draw_unit_id -- check the task where preferred_draw_unit_id equals this value or LV_DRAW_UNIT_NONE

返回:

tan available draw task or NULL if there is no any

uint32_t lv_draw_get_dependent_count(lv_draw_task_t *t_check)

Tell how many draw task are waiting to be drawn on the area of t_check. It can be used to determine if a GPU shall combine many draw tasks into one or not. If a lot of tasks are waiting for the current ones it makes sense to draw them one-by-one to not block the dependent tasks' rendering

参数:

t_check -- the task whose dependent tasks shall be counted

返回:

number of tasks depending on t_check

lv_layer_t *lv_draw_layer_create(lv_layer_t *parent_layer, lv_color_format_t color_format, const lv_area_t *area)

Create a new layer on a parent layer

参数:
  • parent_layer -- the parent layer to which the layer will be merged when it's rendered

  • color_format -- the color format of the layer

  • area -- the areas of the layer (absolute coordinates)

返回:

the new target_layer or NULL on error

void *lv_draw_layer_alloc_buf(lv_layer_t *layer)

Try to allocate a buffer for the layer.

参数:

layer -- pointer to a layer

返回:

pointer to the allocated aligned buffer or NULL on failure

void *lv_draw_layer_go_to_xy(lv_layer_t *layer, int32_t x, int32_t y)

Got to a pixel at X and Y coordinate on a layer

参数:
  • layer -- pointer to a layer

  • x -- the target X coordinate

  • y -- the target X coordinate

返回:

buf offset to point to the given X and Y coordinate

lv_draw_task_type_t lv_draw_task_get_type(const lv_draw_task_t *t)

Get the type of a draw task

参数:

t -- the draw task to get the type of

返回:

the draw task type

void *lv_draw_task_get_draw_dsc(const lv_draw_task_t *t)

Get the draw descriptor of a draw task

参数:

t -- the draw task to get the draw descriptor of

返回:

a void pointer to the draw descriptor

void lv_draw_task_get_area(const lv_draw_task_t *t, lv_area_t *area)

Get the draw area of a draw task

参数:
  • t -- the draw task to get the draw area of

  • area -- the destination where the draw area will be stored

struct lv_layer_t

Public Members

lv_draw_buf_t *draw_buf

Target draw buffer of the layer

lv_area_t buf_area

The absolute coordinates of the buffer

lv_color_format_t color_format

The color format of the layer. LV_COLOR_FORMAT_...

lv_area_t _clip_area

NEVER USE IT DRAW UNITS. USED INTERNALLY DURING DRAW TASK CREATION. The current clip area with absolute coordinates, always the same or smaller than buf_area Can be set before new draw tasks are added to indicate the clip area of the draw tasks. Therefore lv_draw_add_task() always saves it in the new draw task to know the clip area when the draw task was added. During drawing the draw units also sees the saved clip_area and should use it during drawing. During drawing the layer's clip area shouldn't be used as it might be already changed for other draw tasks.

lv_draw_task_t *draw_task_head

Linked list of draw tasks

lv_layer_t *parent
lv_layer_t *next
bool all_tasks_added
void *user_data
struct lv_draw_dsc_base_t

Public Members

lv_obj_t *obj
lv_part_t part
uint32_t id1
uint32_t id2
lv_layer_t *layer
size_t dsc_size
void *user_data